There have been other designs of composite or multi-layer fuel tanks. One other example is disclosed in U.S. Pat. No. 3,968,896 to Giacoletti et al. The Giacoletti patent has an inner enclosure of elastomeric material surrounded by a conventionally "clam-shell" assembled metal shell. Outwardly projecting edge portions mate together near the tank's mid-portion in clam-shell fashion and are secured together by conventional but undisclosed means.
The subject composite fuel tank includes an elastomeric inner enclosure. In a preferred generally six-walled configuration, the inner enclosure is reinforced and supported by a generally "cup-shaped" and open topped metal outer housing and a metal top member. The top member has a peripheral edge which depends therefrom and overlies the upper edge portion of the other member's side walls. An integral strip projecting outward from the exterior of the elastomeric enclosure extends between the two edge portions of the outer housing and is compressed therebetween for a good sealing fit.
The aforedescribed fuel tank structure presents a particularly easy to assemble composite fuel tank. In addition, when its top member is secured to a generally flat and horizontally extending vehicle structure by strap fastening extending about the outer housing thereto, the composite fuel tank is made particularly secure and rigid. An advantage of providing a strip portion of the elastomeric enclosure between overlying edges of the top and sides of the rigid outer enclosure is that this tends to provide a good seal and maintains the two layer top wall and the side wall structures in close side-by-side relation to one another.
Accordingly, an advantage of the subject invention is the provision of a two-layered enclosure with a flexible inner layer secured to a more rigid outer layer by means of an integral strip of the inner layer which is pressed between overlying edge portions of the outer layer.
Another advantage of the subject invention is the provision of a two layered composite fuel tank including a flexible elastomeric inner enclosure which is enclosed within a more rigid outer enclosure consisting of a bottom and side walled member and a mating top walled member with an integral portion of the inner elastomeric enclosure secured between overlying portions of the two outer members.